CTLA-4 +49 A/G gene polymorphism in Croatian and Slovenian multiple sclerosis patients.

Polymorphisms in the CTLA-4 gene are known to be important in several autoimmune diseases, including multiple sclerosis (MS). Previous studies on the impact of CTLA-4 +49 A/G gene polymorphism have given contradictory results. We investigated the possible influence of this polymorphism on MS susceptibility and disease behaviour in Croatian and Slovenian populations. Genotyping was performed in 367 patients with MS and 480 control subjects using PCR-RFLP method. The G allele was present in 216 (58.9%) patients with MS vs. 282 (58.7%) healthy controls (P = 0.975, OR = 1.01, 95% CI = 0.76-1.32). No significant differences were observed in CTLA-4 +49 A or G allele distribution between patients and controls, indicating that this polymorphism does not influence susceptibility to MS in the surveyed populations. No correlation was observed between G allele carrier status and age at disease onset, disease course or severity.